1. Field of the Invention
In one aspect, this invention relates to a method for disposing of filter media which is contaminated with a hydrocarbonaeous residue. In another aspect, this invention relates to a method of disposing of filter media which has deposited thereon an oily remainder of filtrate. In still another aspect, this invention relates to an apparatus for filter media disposal.
2. Description of the Related Art
Filters are used in petroleum refining to remove undesired substances from selected process streams. For example, waxy compounds, principally of a paraffinic structure, can be filtered from fuel blending streams to enable a fuel product to meet pour point specifications. In addition, high molecular weight, heavy polynuclear aromatic compounds can be filtered from cool hydrocracker effluent streams to remove such heavy compounds and to avoid precipitation of such heavy compounds in downstream process coolers, avoiding cooler fouling when the streams are then further cooled and recycled.
Filters used in refineries, therefore, may have a wide variety of hydrocarbonaeous material deposited upon or entrained by the filter media. Disposal of such filters presents problems. Contaminated filters may be classified as hazardous wastes, subject to special handling and storage considerations and limitations upon ground transportation and other shipping.
Prior art practices for filter disposal have included processing to allow reuse. Treatment of the filter media by fluid washes of the media or solvent extractions of the deposits upon the media can remove, in some instances, at least a portion of the hydrocarbonaeous deposits. To allow reuse of spent wash fluids and solvents, contaminated wash fluids and solvents are treated by distillations, extractions or other separation steps to remove the hydrocarbonaeous materials from the wash fluids or solvents. Such separation processes have special environmental considerations associated with treatment of and disposal of the extracted hydrocarbonaeous materials. In addition, for filters used in some refinery applications, fluid washes and solvent extractions are not effective or efficient to treat contaminated filter media.